feat: Expose billing periods with invoice object

lago_python_client/models/__init__.py

@@ -7,6 +7,10 @@
     BillableMetricEvaluateExpression as BillableMetricEvaluateExpression,
     BillableMetricEvaluateExpressionResponse as BillableMetricEvaluateExpressionResponse,
 )
+from .billing_period import (
+    BillingPeriodResponse as BillingPeriodResponse,
+    BillingPeriodsResponse as BillingPeriodsResponse,
+)
 from .charge import (
     Charge as Charge,
     Charges as Charges,

lago_python_client/models/billing_period.py

@@ -0,0 +1,18 @@
+from typing import List
+
+from lago_python_client.base_model import BaseResponseModel
+
+
+class BillingPeriodResponse(BaseResponseModel):
+    lago_subscription_id: str
+    external_subscription_id: str
+    lago_plan_id: str
+    subscription_from_datetime: str
+    subscription_to_datetime: str
+    charges_from_datetime: str
+    charges_to_datetime: str
+    invoicing_reason: str
+
+
+class BillingPeriodsResponse(BaseResponseModel):
+    __root__: List[BillingPeriodResponse]

lago_python_client/models/invoice.py

@@ -2,6 +2,7 @@
 
 from lago_python_client.base_model import BaseModel
 
+from .billing_period import BillingPeriodsResponse
 from .credit import CreditsResponse
 from .customer import CustomerResponse
 from .fee import FeesResponse
@@ -118,6 +119,7 @@ class InvoiceResponse(BaseResponseModel):
 
     file_url: Optional[str]
     customer: Optional[CustomerResponse]
+    billing_periods: Optional[BillingPeriodsResponse]
     subscriptions: Optional[SubscriptionsResponse]
     fees: Optional[FeesResponse]
     credits: Optional[CreditsResponse]

tests/fixtures/invoice.json

@@ -97,6 +97,18 @@
         }
       ]
     },
+    "billing_periods": [
+      {
+        "lago_subscription_id": "1a901a90-1a90-1a90-1a90-1a901a901a90",
+        "external_subscription_id": "LAG-EXT-1234",
+        "lago_plan_id": "1a901a90-1a90-1a90-1a90-1a901a901a90",
+        "subscription_from_datetime": "2025-02-00T00:00:00Z",
+        "subscription_to_datetime": "2025-02-28T23:59:59Z",
+        "charges_from_datetime": "2025-01-00T00:00:00Z",
+        "charges_to_datetime": "2025-01-31T23:59:59Z",
+        "invoicing_reason": "subscription_periodic"
+      }
+    ],
     "subscriptions": [
       {
         "lago_id": "b7ab2926-1de8-4428-9bcd-779314ac129b",